Oleg, If you have access to the admin ui, you will need to check to see if the tunnel is being closed before the following error message. It could be possible HC is unable to reach the PCS device due to the tunnel is already closed. Another possibility is HC connection is being sent to another PCS device. This may occur if you have a load balancer distributing load across multiple PCS gateway. Both the tunnel and HC connection must remain on the same device.
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